Conventionally, toner in the form of fine powder is used as a developer for image formation in the image forming apparatus such as an electrophotographic copying machine, a printer or the like. It has been conventional that toner is supplied from a toner supply container set in the image forming apparatus to the image forming apparatus with consumption of the toner in the image forming apparatus.
With respect to such a toner supply container, it is proposed and implemented to keep the toner supply container set within the image forming apparatus, and to discharge the toner gradually.
As such a conventional-type toner supply container, it has been proposed that a toner supply container mounted an the image forming apparatus is rotated to open and close a shutter on the apparatus main assembly side (Japanese Laid-Open Patent Applications Nos. Hei 07-199623, Hei 10-48938, and Hei 10-55103). More specifically, an opening projection for opening the apparatus shutter and a closing projection for closing the apparatus shutter are provided at a peripheral surface of the toner supply container and the toner supply container is rotated to open and close the apparatus shutter in such a state that these projections are configured to interpose the apparatus shutter therebetween.
In order to simplify a constitution for opening and closing the apparatus shutter of the image forming apparatus compared with the above described constitution of the toner supply container, Japanese Laid-Open Utility Model Application No. Sho 63-86652 has proposed a toner supply container, at a peripheral surface thereof, provided with projections for effecting both of opening and closing operations. More specifically, each of two projections provided at both longitudinal end portions of the toner supply container at a peripheral surface is engaged with an associated hole provided in an apparatus shutter of an apparatus main assembly. In such a constitution, the toner supply container is rotationally moved but the apparatus shutter is linearly moved vertically. However, it is difficult to design the constitution so that the projections of the toner supply container are engaged into the holes of the apparatus shutter with reliability. In the case where the projections are forcedly engaged into the holes, there is a possibility of breakage of a shutter mechanism. It is also similarly difficult to ensure such a constitution that the apparatus shutter is pushed up to be reliably closed and the projections of the toner supply container are released from the holes of the apparatus shutter with reliability.